This research project involves the prospective study of a wide range of psychological factors hypothesized to affect the fertility behavior of women during their childbearing years. There are three groups of women being studied: an unmarried group; a just-married group; and a just-mothered group (first child). In each group there are thirty-five women at each age level from ages 18 through 27. Thus, the study involves 1050 experimental subjects. These women are interviewed for an hour and a half and given a battery of psychological tests, including two general personality inventories, a sexual attitude questionnaire, a contraceptive attitude questionnaire, a maternal attitude questionnaire, a feminine interest questionnaire, and a sexual and contraceptive knowledge test. Spouses of the just-married and just- mothered groups are also given one of the personality inventories and a spouse attitude questionnaire which briefly covers most of the behavioral domains explored in more detail with the woman. The study sample has been selected randomly from the San Francisco Bay area. A control group of 210 women (70 from each of the three groups) is also included. This group does not undergo antecedent interview and testing but is followed up in the same manner as the experimental group. The follow-up period covers five years. Once each year for that duration, each woman will be contacted by telephone and interviewed briefly regarding significant intervening fertility events. At the end of the five-year period, the women will be re-interviewed and retested. This study will provide longitudinal information about the effects of psychological characteristics at different points in the life cycle upon subsequent fertility events such as the frequency and spacing of conception and childbirth. It will also allow a prospective psychological study of other behaviors such as marriage, divorce, abortion, and sterilization which have a direct bearing upon subsequent fertility.